Pest control hub

What does it look like?

Both species of wild ginger are non-woody perennials, growing up to 2m tall from thick-branching rhizomes (swollen underground stems). Their dense underground root system spread up to one metre deep excluding all other species. Both species produce shiny leaves 20 to 45cm long.

Kahili ginger flowers January to March and produces scented, lemon and yellow flowers with conspicuous red stamens, followed by fruiting spikes with fleshy orange fruits. Yellow ginger produces scented, cream coloured flowers in clusters, from May to June and does not produce fruit.

Both species prefer forest environments, where soils are fertile and damp, thus wild ginger has been termed a 'forest invader'. Areas where it can commonly be seen growing include forests, streamsides, alluvial forest, light gaps and gullies. It cannot tolerate very dry or rocky areas, due to the generally low fertility of the soil in such environments.

Why is it a problem?

Wild ginger can still successfully multiply when rhizomes are damaged. Young plants are very palatable to livestock, and both species tend to invade all areas where stock are excluded, including within native bush and on road sides and riverbanks. Due to it's all smothering nature, it will eventually replace all other species, being extremely shade tolerant, somewhat tolerant of frost and drought and can withstand immersion in sea water.

Control Methods

Physical control

Small seedlings can be hand pulled and disposed of carefully.

Small clumps can be dug out, as long as all of the root system is removed and disposed of safely. Rhizomes can be placed in a black plastic bag and rotted, or placed in a weak herbicide mix, crushed, dried then burned. Larger clumps should be sprayed.

When removing kahili ginger, remove flower heads as a stopgap before spraying or removing the whole plant. This won’t kill the plant but will stop it from seeding that year. Burn the seed heads.

Related Links

The NPPA is designed to prevent the sale, distribution and propagation of a set list of pest plants (the Accord list) within New Zealand. If allowed to spread further, these pest plants could seriously damage the New Zealand economy and environment.

Sustained control plants are plant pests that are widespread in suitable habitat throughout the region. The intention is to reduce pest densities so that impacts on the community and the environment are decreased.

An unwanted organism is any organism that's capable of causing harm to natural or physical resources (like forests and waterways) or human health. A number of introduced pests in New Zealand are classed as unwanted.

Under Section 52 and 53 of the Biosecurity Act 1993 no person can sell, propagate, breed, distribute or otherwise spread any pest in this Plan, or unwanted organism. Not complying with Section 52 or 53 is an offence under the Act, and may result in penalties noted Section 157(1).

Good Neighbour Rule: Land occupiers within Northland must destroy all Wild ginger within 10 metres of an adjacent or nearby property, where the adjacent or nearby land occupier is taking reasonable measures to manage wild ginger on their property or its impacts on pastoral production or environmental values. This Good Neighbour Rule will be enforced on receipt of a complaint from a directly-affected land occupier.

Land occupiers within Northland must destroy all wild ginger in the operational areas of a quarry.